1. Field of the Invention
The present invention relates to flood protection, and is particularly concerned with providing a device for preventing flood water from entering a building through a doorway or gateway.
2. Discussion of the Background
Not all of the damage done to a building by flooding is caused by the flood waters themselves, but by the deposition of sediments carried in the flood waters, and contamination by micro-organisms present in the flood waters. In areas susceptible to periodical flooding, such as buildings set close to rivers or near the sea, conventional measures adopted to attempt to prevent the ingress of flood waters or tidal surges include the placing of temporary barriers across the doorways of buildings, or the erection of permanent raised thresholds which extend above the expected level of the water. The most commonly used temporary barrier is a sandbag barrier, which must be placed in position before flood water rises over the threshold height.
While they are effective to keep out the flood waters for an initial period, sandbags soon become waterlogged and allow water to enter the building. The provision of permanent raised thresholds against flood waters is an inconvenience in the use of the building, as it restricts access to the building.
A further disadvantage of the temporary barriers commonly used against flood waters is that advance warning of the flood must be given to the occupant or attendant of the building, so that the barriers may be placed in position before the waters rise. Buildings which are unoccupied, or in which the occupants are asleep, are often inundated for want of the placement of such temporary barriers.
It is an objective of the present invention to provide a flood protection device which overcomes the disadvantages of the prior art, and allows unhindered access to the building while providing protection from the ingress of flood waters without the need for manual intervention.
A further objective of the present invention is to provide a barrier which can extend across the doorway of a building, and will deploy itself effectively at time of flood to prevent flood water from entering the building.
A further objective of the present invention is to provide an improved sealing means for such a flood protecting device, operable to form a water tight seal between the flood protection device and the wall of a building in which it is installed.
It is a yet further objective of the present invention to provide an active sealing means which employs the hydro-static pressure of the flood water to effect a water tight seal between the flood protection device and the building.
According to the present invention, there is provided a flood protection device to close an opening in a wall against the passage of flood water through the opening, the device comprising a float which lifts a collapsible barrier out of a stored position below the opening to a deployed position wherein the barrier seals at least the lower part of the opening.